Ted Geisel, better known as Dr. Seuss, wrote and helped design this eccentric fantasy about a young boy named Bart (Tommy Rettig) who, like most young boys, doesn't enjoy his piano lessons with the mean-spirited Dr. Terwilliker (Hans Conried). He figures his time would be better spent playing baseball with his friends or helping his grown-up buddy Arthur Zabladowski (Peter Lind Hayes), a plumber. One night, while fast asleep, Bart has a long and remarkable dream in which he's trapped in the kingdom of the fearsome Dr. T, who has enslaved hundreds of little boys, forcing them to practice on the world's largest piano until they drop. With the help of a friendly plumber, Bart plans a revolt that will topple Dr. T's evil empire once and for all.